This will allow us to grab check results or more interesting things in
the future, if we decide that modules can have return values for more
types of things. Or this may go away and checks will use the reporting
interface like everything else.
The auxiliary report mixin overrides some of the methods in
Metasploit::Credential, which is fine in framework, but causes issues in
projects relying on the base behavior of Metasploit::Credential. This
changes the include scope from global to just whatever includes the
external module mixin.
Changes from a "hope we get at most one message at a time" model to
something beginning to resemble a state machine. Also logs error output
and fails the MSF module when the external module fails.
adfoster-r7